The sex aid, similar to the ‘geisha balls’ used by the books’ central character Anastasia Steele, has also flown to the top of Amazon.com’s list of best-selling ‘sexual wellness’ products.

The company attributes this new success to the erotic books, which contain scenes putting products like Luna Beads in the spotlight.

Furthermore, Britain’s biggest online retailer of sex toys lovehoney.co.uk has reported that their £8.99 nipple clamps have now become the most popular type of bondage toy sold on their website, beating out traditional bondage items like handcuffs and blindfolds.

In March they sold just over 200 pairs – in June they sold a staggering 1,214, a leap of 400 per cent.

Sales of the website’s own love balls are also up 400 per cent since March, and sales of whips – which also play a big part in the books – have more than doubled: in March they sold 300, in June 671.

Similarly, their £14.99 satin wrist restraints are up from 350 pairs in March to 595 sold in June.

Tie me up: lovehoney.co.uk have reported that wrist restraint sales are up from 350 pairs in March to 595 in June

Matthew Curry, head of e-commerce for Lovehoney.co.uk, said: ‘Britons are definitely becoming kinkier as a result of the Fifty Shades of Grey effect.

Sales boom: Nipple clamp sales have spiked by 400% on lovehoney.co.uk

‘A lot of people may not even have known that these sort of erotic toys existed before reading the book.

‘Most of these new customers are first time buyers.

‘The split is around 60 per cent women, 40 per cent men.

‘But we think there are a lot of couples who are experimenting after the female partner has read the book.

‘They’re buying stuff together for role play in the bedroom.

‘Up and down the country British couples are recreating the sexual adventures of Anastasia Steele and Christian Grey!

‘But what’s really interesting is that we’re seeing the buying behaviour change as a result of the book.

‘A lot of first time customers especially appear to have been excited and emboldened by the book and are experimenting.’

Ouch: Sales of whips at lovehoney.co.uk have doubles in the past few months

LELO’s version of the ‘Ben Wa’ or ‘Geisha’ balls, used by the novel’s leading lady, are high-quality ‘love beads’ which are worn to help strengthen the pelvic floor muscles.

They have a variety of health benefits from supporting women preparing for and recovering from childbirth, to maintaining bladder control, and conditioning the muscles.

One customer review of the beads on Yahoo! says: ‘If your typical sex toy is a Ford, the LELO line offers you the Ferrari… What separates Luna Beads from other Kegel exercisers or Ben Wa’s is easy — it gives you a versatile experience.’

Another customer even admitted to using the beads at work: ‘Simply walking briskly around the office made the beads work even harder, giving my muscle a little extra workout…’

Luna beads are available in two sizes: Classic – recommended for women over 30 years old and those who have experienced childbirth – and Mini – recommended for women under 30 years old who have never experienced childbirth.

Costing £33, each set includes two 28g and two 37g beads which can be combined in the silicone harness for a more tailored routine.

Pleased as punch: Characters in the books by EL James, pictured, use love beads, and her readers have been keen to see what all the fuss is about